Update Selection IDL TODOs to match nullability change in spec

Update Selection IDL TODOs to match nullability change in spec

The node arguments of collapse and setPosition were made nullable:
https://github.com/w3c/selection-api/issues/64

Also move out the optional arguments issues into a single comment:
https://github.com/w3c/selection-api/issues/30

BUG=391673
R=yoichio@chromium.org

Committed: https://crrev.com/062f1c74e4f2fd79d0a85bddc046db9c17016ed3
Cr-Commit-Position: refs/heads/master@{#368825}

[philipj_slow, 2016-01-11 09:48:09]

The CQ bit was checked by philipj@opera.com to run a CQ dry run

[commit-bot: I haz the power, 2016-01-11 09:48:29]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1576863002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1576863002/1

[commit-bot: I haz the power, 2016-01-11 11:03:58]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-01-11 11:03:59]

Dry run: This issue passed the CQ dry run.

[yoichio, 2016-01-12 05:14:06]

lgtm

[philipj_slow, 2016-01-12 08:24:26]

The CQ bit was checked by philipj@opera.com

[commit-bot: I haz the power, 2016-01-12 08:24:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1576863002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1576863002/1

[commit-bot: I haz the power, 2016-01-12 08:42:48]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-01-12 08:43:05]

Failed to apply the patch.

[commit-bot: I haz the power, 2016-01-12 08:44:29]

Description was changed from

==========
Update Selection IDL TODOs to match nullability change in spec

The node arguments of collapse and setPosition were made nullable:
https://github.com/w3c/selection-api/issues/64

Also move out the optional arguments issues into a single comment:
https://github.com/w3c/selection-api/issues/30

BUG=391673
R=yoichio@chromium.org
==========

to

==========
Update Selection IDL TODOs to match nullability change in spec

The node arguments of collapse and setPosition were made nullable:
https://github.com/w3c/selection-api/issues/64

Also move out the optional arguments issues into a single comment:
https://github.com/w3c/selection-api/issues/30

BUG=391673
R=yoichio@chromium.org

Committed: https://crrev.com/062f1c74e4f2fd79d0a85bddc046db9c17016ed3
Cr-Commit-Position: refs/heads/master@{#368825}
==========

[commit-bot: I haz the power, 2016-01-12 08:44:29]

Patchset 1 (id:??) landed as
https://crrev.com/062f1c74e4f2fd79d0a85bddc046db9c17016ed3
Cr-Commit-Position: refs/heads/master@{#368825}